Retractors are used in surgery to keep the tissues on either side of an incision apart thereby opening the surgical site. In addition, they are used to move intervening organs out of the way and to hold them so the surgeon has a clear view of the surgical site. However, retraction is limited by the length and width of the blade of the retraction instrument. In some cases, multiple retractors are necessary to maintain a long incision; this is particularly true in the case of spinal surgery. The presence of multiple retractors along the length of the incision can present problems such as entanglement of other instruments or tissues in the mechanisms of those retractors, or they can simply get in the way of the surgeon.
A variety of retractors have been developed in attempts to provide both better retraction and to alleviate some of the other problems encountered. For example, U.S. Pat. No. 2,473,266, Wexler discloses a self retaining abdominal retractor in which a frame surrounds the surgical site and provides means for attaching retractor blades to it. However, this frame is limited in its size and remains above and surrounding the surgical site where other instruments or materials may get caught on it. U.S. Pat. No. 5,052,373, Michelson, discloses a spinal retractor which includes a frame comprising a pair of spreadable arms on which pairs of blade sets are self engaging. Although this device is adjustable, its reach is limited by the length of the arms.
The present invention overcomes the problems and limitations of the prior art by providing an auxiliary surgical retractor blade system which is extremely variable in length and which can be used with most types of prior retraction instruments, including that of Michelson, to provide a free floating buttress which is pressed against the tissues of the surgical wound by a minimum of conventional retractor instruments. The system also provides for variability in blade height making it useful for deep incisions.